US 12,422,952 B2
Touch detection circuit
Jia-Ming He, Tainan (TW); and Yaw-Guang Chang, Tainan (TW)
Assigned to HIMAX TECHNOLOGIES LIMITED, Tainan (TW)
Filed by HIMAX TECHNOLOGIES LIMITED, Tainan (TW)
Filed on Jan. 9, 2024, as Appl. No. 18/408,536.
Claims priority of provisional application 63/537,823, filed on Sep. 12, 2023.
Prior Publication US 2025/0224835 A1, Jul. 10, 2025
Int. Cl. G06F 3/041 (2006.01); G06F 3/044 (2006.01)
CPC G06F 3/0418 (2013.01) [G06F 3/04166 (2019.05); G06F 3/0446 (2019.05)] 11 Claims
OG exemplary drawing
 
1. A touch detection circuit, comprising:
a plurality of driving signal generators, wherein the plurality of driving signal generators are divided into a plurality of driving signal generator groups, each of the plurality of driving signal generator groups comprises at least one of the driving signal generators,
wherein the plurality of driving signal generators respectively generate a plurality of driving signals, and a frequency of each of the driving signals in one of the plurality of driving signal generator groups is different from a frequency of each of the plurality of driving signals in another one of the plurality of driving signal generator groups,
wherein in each of the plurality of driving signal generator groups, the plurality of driving signals are divided into at least one first driving signal and a plurality of second driving signals, waveforms of the plurality of second driving signals are same, and waveform of the at least one first driving signal is different from the waveforms of the plurality of second driving signals,
wherein the plurality of driving signal generators respectively provide the plurality of driving signals to a plurality of touch sensing pads; and
a plurality of sensing signal receivers, respectively receiving a plurality of sensing signals from corresponding touch sensing pads, and generating touch sensing information according to the plurality of sensing signals,
wherein each of the plurality of signal sensing receiver comprises:
a signal adder, summing the corresponding sensing signal to obtain a summation signal;
an analog front-end circuit, coupled to the signal adder, processing the summation signal to generate a processed signal; and
a plurality of filters, coupled to the analog front-end circuit, wherein the plurality of filters respectively perform signal filtering operations on the processed signal to respectively generate a plurality of filter signals,
wherein the plurality of filters respectively have a plurality of different filter bands, and any two of the plurality of filter bands are not overlapped,
wherein the plurality of filter bands are respectively set according to the frequencies of the plurality of driving signals of the plurality of driving signal generator groups.